俱舍論頌疏論本 7.51

7.51

餘從五生四者，餘謂無學心，此無學心從五心生，能生四心。從五生者，謂三界善、學、無學心。能生四者，於前五上唯除學心。

"The rest arises from five and gives rise to four": "the rest" means the mind of a non-learner. This mind of a non-learner arises from five minds and can give rise to four minds. Arising from five means the wholesome of the three realms, the learner, and the non-learner minds. Being able to give rise to four means excluding only the learner mind from the preceding five.